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Some charac ter ist ics of gametophyt ic progeny are determined by genes (di str ibution bei ng Mendelian), some are determined by cytoplasm, the result in maternal inheritance, some by the combined influence of genes and cytoplasm. 10. Evolutionary Trends in Reproductiv e Biology The basic system of reproductive strategies is almost similar in mosses and hepatics involving  primitive features, for example perennial, dioecious gametophytes, absence of specialized asexual propagule s, immersed capsul e, reduce d peristome of capsule and larger spores. A spe cific combination of the se pri mi tiv e and adva nce features ins usuali y seen in par tic ula r situations (Longton and Schuster 1983). Evolution in life history strategies of mosses has been extensively studied by During (1979). He has emphasized habitat stability, colony longevity, age at first reproduction, spore size and effort of reproduction by sexual and asexual means. He defined six main life history strategies in mosses. 1. Perenn ia l Sta ye r : which includes perennial and predominentlydioecious taxa with lover localized sexual reproduction efforts. Low rate of asexual propagules, less than 20 µm spore size e.g.  Leucobryum glaucum, Hylocomium splendens etc.; 2. Pe rennia l Sh ut tl e : characterized by pluriennial (5-10 yrs), monoecious or dioecious taxa havi ng age of fi rst repr oducti on asexu al : 1- 2 yr s, and sexua lup to 5 yr s, se xua l reproduction efforts are variable however, asexual reproduction efforts is high in the case of lo w sexual reproduc ti on ef fort, 25 µm spor e size, e.g. Orthotrichum spp.,  Macromitrium spp. etc.; 3. Colonist: including monoecious or dioecious taxa surviving from one to a few years (pa uci enni als ) wit h the age of fi rst ase xua l reproduct ion mor e tha n 1 year , sexual reprod uctio n at the age of 2-3 years, variable effort of sexual and asexual reproducti on, spore size 20 µm. e.g.  Bryum bicolor, Grimmia pulvinata ; 4. Short- li ve d Sh uttle : including many monoecious, pluriennel or pauciennial taxa having first reproduction at 2-3 years of age, high rate of sexual reproduction at 2-3 years of age, high rate of sexual reproduction effort and 25 µm size of spores, e.g.  Bryum marratii, Tetraplodon mnioides, etc. 5. An nu al Sh ut tl e : including ephemeral s (pers iste nceof a given colony < 1 year), annual s or pauciennial mostly monoecious taxa having their first sexual reproduction at the age of less than 1 year, which are not restricted to a particular season. Taxa belonging to this category exhibit high efforts of sexual reproduction whereas asexual propagules are rare or absent. Their spore size is more than 25 µm, e.g.  Archidium spp., Ephemerum spp. etc.;

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Some characteristics of gametophytic progeny are determined by genes (distribution being

Mendelian), some are determined by cytoplasm, the result in maternal inheritance, some by the

combined influence of genes and cytoplasm.

10. Evolutionary Trends in Reproductive Biology

The basic system of reproductive strategies is almost similar in mosses and hepatics involving

 primitive features, for example perennial, dioecious gametophytes, absence of specialized

asexual propagules, immersed capsule, reduced peristome of capsule and larger spores. A

specific combination of these primitive and advance features ins usualiy seen in particular 

situations (Longton and Schuster 1983). Evolution in life history strategies of mosses has been

extensively studied by During (1979). He has emphasized habitat stability, colony longevity, age

at first reproduction, spore size and effort of reproduction by sexual and asexual means. He

defined six main life history strategies in mosses.

1. Perennial Stayer : which includes perennial and predominentlydioecious taxa with lover 

localized sexual reproduction efforts. Low rate of asexual propagules, less than 20 µm

spore size e.g. Leucobryum glaucum, Hylocomium splendens etc.;

2. Perennial Shuttle : characterized by pluriennial (5-10 yrs), monoecious or dioecious taxa

having age of first reproduction asexual: 1-2 yrs, and sexualup to 5 yrs, sexual

reproduction efforts are variable however, asexual reproduction efforts is high in the case

of low sexual reproduction effort, 25 µm spore size, e.g. Orthotrichum spp.,

 Macromitrium spp. etc.;

3. Colonist: including monoecious or dioecious taxa surviving from one to a few years

(pauciennials) with the age of first asexual reproduction more than 1 year, sexual

reproduction at the age of 2-3 years, variable effort of sexual and asexual reproduction,

spore size 20 µm. e.g. Bryum bicolor, Grimmia pulvinata;

4. Short-lived Shuttle: including many monoecious, pluriennel or pauciennial taxa having

first reproduction at 2-3 years of age, high rate of sexual reproduction at 2-3 years of age,

high rate of sexual reproduction effort and 25 µm size of spores, e.g.  Bryum marratii,

Tetraplodon mnioides, etc.

5. Annual Shuttle: including ephemerals (persistenceof a given colony < 1 year), annuals

or pauciennial mostly monoecious taxa having their first sexual reproduction at the age of 

less than 1 year, which are not restricted to a particular season. Taxa belonging to this

category exhibit high efforts of sexual reproduction whereas asexual propagules are rare

or absent. Their spore size is more than 25 µm, e.g.  Archidium spp., Ephemerum spp.

etc.;

 

6. Fugitives: these are annual and essentially monoecious taxa having their first sexual

reproduction at the age of < 1 year, with a transient habitat. These taxa exhibit a high

effort of sexual reproduction while asexual propagules are rare or absent with a spore size

less than 20 µm, e.g. Funaria hygrometrica.

The evolution of reproductive strategies in hepatics is almost parallel to that of 

mosses, e.g. trends towards monoecism, immersed, indehiscent capsules and large spores,

comoined with absence of asexual propagules, assemblages of species from both groups

in seasonally arid habitats. For the hepatics, the Bazzania-Anastrophyllum model has

 been suggested (Longton and Schuster 1983) which is a basic model and includes a wide

range of taxa. This model involves all modifications in reproductive modalities involving

linkage of (1) unisexuality, (2) rarity of asexual reproduction devices (gemmae, etc.)

formed by gametophyte, and (3) perennial gametophytes having the capacity to form

clones of indeterminate size and age.

11. Studies on Reproductive Biology in the 21st Century

The significance of studies on reproductive biology of Bryophyte cannot be fully

appreciated till the answers to several fundamental questions are available, e.g. level of 

 ploidy in gametophytes, the role of spores where produced in population maintenance

and dispersal, the rate of inbreeding in monoecious taxa, incidence of sexual reproduction

 by outbreeding to maintain evolutionary effective levels of genetic diversity. Few of 

these topics are being studied, and there needs to be a serios attempt for this potentially

most

Terjemahan :

Beberapa karakteristik keturunan gametophytic ditentukan oleh gen (Mendel menjadi distribusi),

 beberapa ditentukan oleh sitoplasma, hasil dalam warisan ibu, beberapa oleh pengaruh gabungan

gen dan sitoplasma.10. Evolusi Tren Biologi Reproduksi

Sistem dasar dari strategi reproduksi hampir mirip di lumut dan hepatics melibatkan fitur 

 primitif, misalnya abadi, gametophytes dioecious, tidak adanya propagul aseksual khusus, kapsuldirendam, mengurangi peristome kapsul dan spora lebih besar. Kombinasi khusus dari usualiy in

fitur primitif dan muka terlihat dalam situasi tertentu (Longton dan Schuster, 1983). Evolusi

dalam strategi riwayat hidup lumut telah dipelajari secara ekstensif oleh Selama (1979). Dia telahmenekankan stabilitas habitat, umur panjang koloni, usia saat reproduksi pertama, ukuran spora

dan usaha reproduksi dengan cara seksual dan aseksual. Dia ditetapkan enam strategi kehidupan

sejarah utama di lumut.

 

1. Stayer abadi: yang mencakup taksa abadi dan predominentlydioecious dengan kekasih upaya

reproduksi lokal seksual. Rendahnya tingkat propagul aseksual, kurang dari 20 pM misalnya

ukuran spora Leucobryum glaucum, Hylocomium splendens dll;2. Shuttle abadi: taksa ditandai dengan pluriennial (thn 5-10), berumah satu atau dioecious

memiliki usia reproduksi aseksual pertama: 1-2 thn, dan sexualup sampai 5 thn, upaya

reproduksi seksual adalah variabel namun upaya reproduksi aseksual tinggi dalam kasus iniusaha reproduksi rendah seksual, 25 pM ukuran spora, misalnya Orthotrichum spp,

Macromitrium spp.. dll;

3. Penjajah: termasuk taksa berumah satu atau dioecious yang masih hidup dari satu sampai beberapa tahun (pauciennials) dengan usia reproduksi aseksual pertama lebih dari 1 tahun,

reproduksi seksual pada usia 2-3 tahun, usaha variabel reproduksi seksual dan aseksual, ukuran

spora 20 pm. misalnya Bryum bicolor, Grimmia pulvinata;

4. Berumur pendek Shuttle: termasuk berumah satu banyak, pluriennel atau taksa pauciennialmemiliki reproduksi pertama pada usia 2-3 tahun, tingginya tingkat reproduksi seksual pada usia

2-3 tahun, tingginya tingkat upaya reproduksi seksual dan 25 pM ukuran spora, misalnya Bryum

marratii, mnioides Tetraplodon, dll5. Tahunan Shuttle: termasuk ephemerals (persistenceof koloni diberikan <1 tahun), semusim

atau taksa sebagian besar berumah satu memiliki pauciennial reproduksi seksual pertama mereka

 pada usia kurang dari 1 tahun, yang tidak terbatas pada musim tertentu. Taksa termasuk kategoriini menunjukkan upaya yang tinggi sedangkan reproduksi seksual propagul aseksual jarang atau

tidak ada. Ukuran spora mereka lebih dari 25 pM, mis Archidium spp, Ephemerum spp.. dll;

6. Buronan: ini adalah tahunan dan taksa dasarnya berumah satu memiliki reproduksi seksual pertama mereka pada usia <1 tahun, dengan habitat sementara. Taksa ini menunjukkan upaya

yang tinggi reproduksi seksual saat propagul aseksual jarang atau tidak ada dengan ukuran spora

kurang dari 20 pM, misalnya Funaria hygrometrica.

Evolusi strategi reproduksi pada hepatics hampir paralel dengan yang dari lumut, misalnya trenmenuju monoecism, tenggelam, kapsul indehiscent dan spora besar, comoined dengan tidak 

adanya propagul aseksual, kumpulan spesies dari kedua kelompok di habitat musiman gersang.

Untuk hepatics, model Bazzania-Anastrophyllum telah disarankan (Longton dan Schuster 1983)yang merupakan model dasar dan mencakup berbagai taksa. Model ini melibatkan semua

modifikasi dalam modalitas reproduksi yang melibatkan hubungan dari (1) unisexuality, (2)

kelangkaan perangkat reproduksi aseksual (gemmae, dll) yang dibentuk oleh gametofit, dan (3)gametophytes abadi memiliki kapasitas untuk membentuk klon ukuran tak tentu dan usia.

11. Penelitian tentang Biologi Reproduksi di Abad 21

Arti penting dari studi tentang biologi reproduksi Bryophyte tidak dapat sepenuhnya dihargai

sampai jawaban atas pertanyaan mendasar tersedia beberapa, misalnya tingkat ploidi di

gametophytes, peran spora diproduksi di mana pemeliharaan dan penyebaran penduduk, tingkat perkawinan sedarah dalam taksa berumah satu, kejadian reproduksi seksual oleh outbreeding

untuk mempertahankan tingkat efektif evolusi keanekaragaman genetik. Hanya sedikit dari topik 

ini sedang diteliti, dan perlu ada upaya serios untuk ini berpotensi paling